Abstract: A concealment that covers all or a main part of naval vessels and their surroundings and crew, by making provision for coupling a flow of air with an injection of fluid to cause formation of a cloud and to orient the cloud to optimize coverage of the vessel and the surroundings to be protected. A concealment apparatus includes a gas turbine coupled to a conduit discharging a flow of smoke composed of a combustion gas loaded with droplets of fluid in suspension. The conduit includes two branches that emerge on each lateral half-hull of the hull of the vessel. The branches are symmetrical with respect to a vertical symmetry plane of the ship and, through their curvature, have roughly a direction oriented towards the rear of the ship. In this way, the flow of smoke is also oriented towards the rear of the ship.